a human limb; technically the part of the superior limb between the shoulder and the elbow but commonly used to refer to the whole superior limb. arm, branch, limb (noun). any projection that is thought to resemble a human arm.
Vertebrates are the most organized organisms on Earth. They belong to the sub-phylum Vertebrata. They are not the most numerous group of animals, they are the most advanced group of animals.The characteristics that makes vertebrates special are the presence of the spinal cords, vertebrae and notochords.hey belong to the Phylum Chordata. The characteristics of phylum chordata is the presence of notochord, a dorsal hollow nerve cord and paired pharyngeal gill slits. The members of subphylum Vertebrata possess notochord during the embryonic period.
Among the most basic criteria by which animals are sorted is whether or not they possess a backbone. This single trait places an animal into one of just two groups: the vertebrates or the invertebrates and represents a fundamental division among all animals alive today as well as those that have long ago disappeared.here are a few groups of chordates that do not possess a backbone (these organisms are not vertebrates and are instead referred to as invertebrate chordates). The animal classes that are vertebrates include: 1  Jawless fish (Class Agnatha).